A fuel cell system is a power generation system configured to generate and supply electric power to a consumer, thereby covering the consumer's electricity load.
There is a known fuel cell power generation system that is configured such that a fuel cell system as mentioned above is installed inside a building and that is intended to improve the exhaust performance of the fuel cell system (see Patent Literature 1, for example). The fuel cell system disclosed in Patent Literature 1 is a fuel cell system installed and used inside a building provided with an air inlet. The fuel cell system includes: an air introduction port, through which the air inside the building is introduced into the fuel cell system; an air exhaust pipe, through which the air inside the fuel cell system is discharged to the outside of the building; and a ventilator. The ventilator guides the air outside the building into the building through the air inlet, such that the air is further introduced into the fuel cell system through the air introduction port, and such that the air is then discharged to the outside of the building through the air exhaust pipe.
There is also a known fuel cell system that is installed inside a building and that includes a vertically-extending duct for the purpose of improving the performance of discharging an exhaust gas generated by the fuel cell system (see Patent Literature 2, for example). In the fuel cell system disclosed in Patent Literature 2, the duct extends vertically inside the building, and the top end of the duct is positioned outside the building. The duct has a double-pipe structure. A ventilation pipe and an exhaust pipe are connected to the duct, such that each of the exhaust gas and air separately flows through a corresponding one of the inner side and the outer side of the duct.
Further, there is a known fuel cell system configured to prevent freezing of water generated inside a fuel cell (see Patent Literature 3, for example). The fuel cell system disclosed in Patent Literature 3 is configured to cause heat exchange between exhaust air discharged from the fuel cell and supply air supplied to the fuel cell, the supply air being external air, such that the supply air is warmed up through the heat exchange, thereby preventing the freezing.